The present invention relates to a method of conveying packets of cigarettes.
The present invention may be used to advantage for transferring packets of cigarettes from a cellophaning machine to a cartoning machine, to which the following description refers purely by way of example.
In cigarette packing systems comprising a cellophaning machine and a cartoning machine connected in series, the packets of cigarettes are fed between the two machines by means of a packet conveying unit comprising a screw transfer device rotating about an axis of rotation, and a guide which has an input and an output for the packets, is located outside the transfer device, and winds about the axis of rotation to cooperate with the transfer device to transfer the packets from the input to the output.
In known systems, the transfer device receives the packets laid flat with the respective end surfaces laterally facing the input of the guide, and comprises a substantially cylindrical core coaxial with the axis of rotation, at least one thread winding about the core, and an unloading conveyor belt device located at the output of the guide to extract the packets in a direction tangent to the thread, and so form a succession of packets with the respective end surfaces contacting one another.
Conveying the packets as described above involves several drawbacks, mainly on account of the operating and functional rigidity of the conveying unit. That is, in addition to requiring an unloading device to extract the packets of cigarettes as described above, a succession of packets such as the one described cannot be formed with the two machines arranged in line. Moreover, should operating changes require a different orientation of the packets at the output as compared with the input, substantially the whole conveying unit must be replaced with another specially designed for the purpose.